The way forward for audio in your Android: Inside Qualcomm’s Snapdragon Sound Lab

Listening to music in your cellphone is greater than a matter of streaming one thing from Spotify and placing on headphones — lots of processing steps happen between your favourite media service, your gadget, and your ears. Qualcomm is considered one of many firms dealing with these steps, significantly in terms of Android telephones utilizing its Snapdragon processors.

I not too long ago visited Qualcomm’s San Diego headquarters and toured its audio lab, the place it develops and refines how Snapdragon-based gadgets deal with music and different audio content material. Whereas there, I additionally tried out a few of the latest options that Qualcomm’s audio platform, Snapdragon Sound, will help on future telephones.

Qualcomm sound areas

Qualcomm’s audio take a look at lab is made up of a number of sections over a number of flooring, all with totally different functions. The purest and most exact sound measurements happen in three laboratory-built acoustic anechoic chambers.

Qualcomm’s acoustic anechoic chamber is designed to permit for full silence (Credit score: Will Greenwald)

Acoustic anechoic chambers are greater than soundproof rooms; they’re successfully anti-sound rooms. They’re designed to permit for full silence by not solely fully blocking out all outdoors noise but in addition stopping any form of sound reflection throughout the area itself. The most important of the lab chambers, a nine-ton field that may match a number of individuals, is mounted on vibration isolators and makes use of large wedge-shaped sections of froth put in on most surfaces to soak up most sound frequencies as much as at about 160Hz.

The lab employs two further smaller chambers of comparable design, every giant sufficient to accommodate a head and torso simulator (HATS), or a human higher body-sized take a look at dummy with microphones designed to precisely simulate the human listening to. Testing is carried out in all three chambers utilizing a HATS, reference microphones to measure speaker output, and reference audio system to measure microphone enter.

To additional take a look at and develop spatial audio expertise, the lab wants to have the ability to document and analyze sound from a number of instructions. To do that, Qualcomm created a take a look at sphere. The geodesic sphere is giant sufficient to carry one particular person and is supplied with 25 audio system that time on the heart from a number of instructions. An engineer (or HATS) could be positioned within the heart of the sphere to obtain the multi-directional audio alerts and consider efficiency.

This spatial audio sphere is giant sufficient for somebody to stroll inside and options 25 audio system pointing on the heart from totally different instructions (Credit score: Will Greenwald)

Different areas are arrange across the lab for extra lifelike testing, together with three soundproofed (however not anechoic) rooms for analyzing how voice-assist gadgets like good audio system course of voices. There are additionally areas organized as workplaces and dwelling rooms, together with one the place Qualcomm demonstrated a few of the superior options of Snapdragon Sound.

Snapdragon Sound’s new tips

Snapdragon Sound is Qualcomm’s audio platform, a set of unifying applied sciences in telephones, headphones, and different audio gadgets. Snapdragon Sound allows options reminiscent of lossless audio over Bluetooth, spatial audio with head monitoring, and Auracast broadcast audio between a number of units of transmitters. Qualcomm’s Snapdragon Sound director Mike Canevaro confirmed me these three options.

Lossless audio by way of Bluetooth

Lossless audio over Bluetooth is simply what it seems like: the power to take heed to lossless audio recordsdata over Bluetooth. This isn’t simple to perform as a result of restricted information bandwidth of Bluetooth, which is why nearly all Bluetooth gadgets use lossy audio codecs as an alternative. Qualcomm’s AptX Lossless codec is likely one of the few exceptions to this rule: it is able to upscaling audio alerts to lossless high quality when wi-fi situations can deal with it (for instance, when there aren’t any different gadgets close by) and scales the sign at lossy high quality in crowded wi-fi environments. AptX Lossless is an evolution of AptX Adaptive, a earlier AptX codec that may additionally regulate sign high quality on the fly.

This Head and Torso Simulator (HATS) is a human higher body-sized take a look at dummy with microphones designed to precisely simulate human listening to

“At this time, we proceed to be the one firm on the earth that may present a lossless answer by way of Bluetooth,” Canevaro mentioned. “Utilizing our AptX Adaptive encoding, we’re really capable of scale as much as 1.2 megabits per second, so you’ll be able to really stream losslessly over the hyperlink. At this time we’re doing [24-bit/96kHz] excessive decision audio, 16-bit/44.1 lossless CD and 16-bit/48 lossless.”

I listened to some AptX Lossless audio over Bluetooth utilizing Qualcomm growth {hardware}. Audio readability and element could be as a lot a matter of the tools because the sign being despatched to it, and even high-quality lossy audio can sound glorious with the suitable headphones. Nevertheless, the take a look at tracks I listened to on Qualcomm’s earphones sounded extremely detailed and delicate over Bluetooth, similar to, even, high-end wired earphones. My first impression is that AptX Lossless has a big sign high quality benefit over each AAC and LDAC. After all, like all codecs, AptX Lossless requires each cellphone and headphone help.

Spatial audio with head monitoring

I additionally tried Snapdragon Sound’s spatial head-tracking audio function. The platform helps sound sources from a number of instructions, not simply mixing audio to simulate directional imaging, however utilizing movement sensors within the headphones to regulate these sources on the fly based mostly on how you progress your head.

The demo was a easy expertise promotional video with spatial audio info encoded inside it. The narrator within the video seemed to be talking straight in entrance of me, and as I turned my head to the left and proper of her her voice moved between my ears to remain anchored relative to my place. It was an efficient demo for horizontal placement, although head monitoring did not go very effectively in vertical; tilting the pinnacle up and down did not regulate the sound as realistically as after I rotated it left and proper.

We have already seen head-tracking spatial audio within the Apple AirPods Max and AirPods Professional and a few gaming headsets just like the Audeze Mobius, whereas the sort of audio processing is frequent in digital actuality headsets. Snapdragon Sound is a promising technique to deliver this expertise to Android gadgets by way of Bluetooth, though headphones with built-in movement sensors shall be required to work. And, like different device-based head-tracking spatial audio, the Snapdragon Sound implementation works with all kinds of standardized spatial audio content material, reminiscent of Dolby Atmos.

Auracast on Snapdragon Sound (Credit score: Will Greenwald)

Auracast: Multipoint public audio

Lastly, Auracast is likely one of the latest options launched by the Bluetooth Particular Curiosity Group (SIG), the requirements group that oversees Bluetooth. Allows Bluetooth headsets to wirelessly join and change between a number of public broadcast gadgets. This function can permit museum guests to entry digital guides for various displays or permit exercise lovers to tune into any of the TVs within the gymnasium simply by tapping their earphones. Auracast differs from headphones that merely help two simultaneous connections as a result of it does not simply pair to at least one (or two) gadgets; as an alternative, it rapidly switches between a probably limitless variety of public broadcast gadgets. Auracast remains to be in its early levels, however Snapdragon Sound will help it.

I examined the Snapdragon Sound implementation of Auracast at Qualcomm’s take a look at lab. Two telephones have been positioned in entrance of me and every began broadcasting by way of Auracast. I inserted the take a look at earbuds and was capable of leap backwards and forwards between the 2 telephones by double-tapping one of many earbuds. It labored virtually completely, though there was a half-second hiccup throughout every change the place I might solely hear sound via the left earbud earlier than each totally kicked in. Nevertheless, this was extremely practical for a tech demo.

The way forward for listening

Whereas all of those options fall beneath the Snapdragon Sound label, every has its personal necessities throughout Snapdragon-powered telephones and headphones to work. Whether or not you need lossless Bluetooth audio, motion-based spatial audio, or Auracast compatibility, implementing every particular person function on a given pair of headphones will rely upon the producer.

Qualcomm creates the chipsets and unifying software program components that allow these options, however you will not really expertise them via your ears till client gadgets begin implementing them. It is clear that Qualcomm is doing lots of work to make this doable, and we’re more likely to see new merchandise that leverage its work within the close to future.

For extra on the expertise that shapes what you hear, try our guides to Bluetooth codecs, equalizers and lossless audio.